docs: def updateUser(self, username, password, fullname, description, email):
          """ Updates a user account in the user store
             Input:
                username - the name of the user. The name must be unique in
                           the user store.
                password - the password for this user.
                fullname - an optional full name for the user.
                description - an optional field to add comments or description
                              for the user account.
                email - an optional email for the user account.
          """
          params = {
              "f" : "json",
              "username" : username
          }
          if password is not None:
              params['password'] = password
          if fullname is not None:
              params['fullname'] = fullname
          if description is not None:
              params['description'] = description
          if email is not None:
              params['email'] = email
          uURL = self._url + "/users/update"
          return self._post(url=uURL, param_dict=params,
                               securityHandler=self._securityHandler,
                               proxy_url=self._proxy_url,
                               proxy_port=self._proxy_port)